Dental drill



M. F. GROEGL June 21, 1949.

DENTAL DRILL 2 sneaks-sheet 1 Filed Aug. 14, 1947 I INVENTOR. Max Grog];

ATTCIRN EYS M. F. GROEGL DENTAL DRILL June 21,.1949.

2 Sheets-Sheet 2 Filed Aug. 14, 1947 n INVENTOR.

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ATTDRN EYS Patented June 21, 1949 DENTAL DRILL Max Francis Griigl, Barranquilla, Colombia Application August 14, 1947, Serial No. 768,551 In France August 14, 1946 1 Claim.

This'invention relates to dental handpieces and particularly means for cooling handpieces while in use, and in particular the invention includes introducing a refrigerant into a comparatively small area inside of a sheath of a handpiece for cooling the handle thereof and burr.

The purpose of this invention is to facilitate grinding in filling teeth by keeping the burr at a comparatively low temperature which substantially eliminates pain and prevents damage to the teeth caused by overheating.

The drilling, milling, and cleaning operations in and on a tooth in combination with friction of the spindle bearings of a handpiece cause heat and when a cavity is in the vicinity of a nerve the heat causes pain. Furthermore excessive heat in a cavity of a tooth originates alterations of the organic components of the tooth causing additional decay that results in the filling becoming loose, necessitating refilling of the same cavity.

With these thoughts in mind this invention contemplates means for applying a refrigerant directly to the tip of a dental handpiece wherein the burr is maintained at a comparatively low temperature in use.

The object of the invention is to provide means for expanding and circulating a refrigerant in the sheath of a dental handpiece without materially increasing the size thereof.

Another object is to provide means for cooling dental handpieces that may be applied to handpieces now in use.

Another object of the invention is to provide a sheath for dental handpieces in which a refrigerant may be expanded for cooling, that may readily be removed and replaced.

A further object of the invention is to provide a dental handpiece having cooling means therein which is of a simple and economical construction.

With the foregoing and other objects in view which will appear as the description proceeds the invention resides in the combination and arrange of parts and in the details of construction hereinafter described and claimed. It being understood that changes in the precise embodiment of the invention herein described may be made within the scope of what is claimed without departing from the spirit of the invention.

In the accompanying drawings forming part of this specification:

Figure 1 is a view showing a dental unit with the handpiece refrigerating device in combination therewith.

Figure 2 is a view showing a refrigerating sheath on a dental handpiece with the handpiece indicated in dotted lines, and with a refrigerant supply tube extending through a suction tube and downward through a sheath to a point spaced from the burr holding chuck of the handpiece, illustrating a vertical section through the refrigerating elements.

Referring now to the drawings wherein like reference characters indicate corresponding parts, the refrigerant cooled dental handpiece of this invention includes an outer tubular casing, an inner casing, a refrigerant supply tube, a suction tube, a burr holding chuck, a connector by which the parts are attached to a handpiece, and a refrigerating unit with suitable connections to a source of current and to the sheath on the handpiece.

As shown in Figure 2 the attachment is formed with an outer tubular casing [0 having an outer protecting sleeve 1 I of insulating material or the like, and the lower end is provided with a cap [2 that holds the outer end of a chuck l3. The inner end of the chuck is mounted in the end of an inner casing M, the upper end of which is provided with a connector IS on the outer surface of which the upper end of the outer casing is also mounted. In this design a compressed or liquified refrigerant is supplied from a refrigerating unit l6 through a tube l1, having an expansion nozzle It in the end thereof, and after being expanded the refrigerant vapor is returned to the unit It through the connection l9, through which the refrigerant supply tube I! also extends.

In Figure 1 the refrigerating unit I6 is shown suspended from an arm 32 of a dental chair 33 with current supplied thereto through an electric cable 34, and the suction connection I9 with the refrigerant supply tube I! therein is suspended from an arm 35 at the upper end of a post 36.

With the parts arranged in this manner the refrigerant is released or expanded at the tip or burr holding end of a dental handpiece so that cooling is directly applied to the burr or tool held therein, and with the burr or tool cooled in this manner substantially all heat from the hearings or cutting or grinding action will be eliminated.

The attachment may readily he slipped over most straight handpieces, and it will be understood that with slight modifications in the parts it may be provided to accomodate handpieces of substantially any type.

The device is described as used for cooling dental handpieces and it will also be understood that the cooling attachment may be used for other instruments or tools or for other purposes.

The connector at the upper end of the attachment is formed with a bead 31 that is held in the head of a handpiece by a latch 38.

It will be understood that other changes may be made in the design or arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

A removable attachment for a dental handpiece, comprising an inner tubular casing, an outer tubular casing concentric with the inner casing and spaced therefrom, an outer protecting sleeve mounted on the outer tubular casing, a tapered cap mounted on the lower end of the outer tubular casing, an inner tubular chuck connecting the lower end of the inner casing with the lower end of the cap, thereby providing an expansion chamber in the lower end of the attachment, a connector for spacing the upper ends of said outer and inner casings and provid- 4 ing means for connecting the attachment to the handpiece, said outer casing having a. return connection adjacent the upper end thereof, and a refrigerant supply tube positioned between the inner and outer casings, whereby a refrigerant may be conveyed through the supply tube into the expansion chamber at the lower end of the attachment, and said refrigerant may be withdrawn, after expanding, through the return connection adjacent the upper end of the attachment.

MAX FRANCIS GRijGL.

REFERENCES CITED The following referenices are of record in the file of this patent:

UNITED STATES PATENTS Name Date Roos July 26, 1938 Pertics Nov. 21, 1944 Number 

